//数组
func main() {
     var a [ 5 ] int
     fmt.Println( "array a:" , a)
  
     a[ 1 ] = 10
     a[ 3 ] = 30
     fmt.Println( "assign:" , a)
  
     fmt.Println( "len:" , len(a))
  
     b := [ 5 ] int { 1 , 2 , 3 , 4 , 5 }
     fmt.Println( "init:" , b)
  
     var c [ 2 ][ 3 ] int
     for i := 0 ; i < 2 ; i++ {
         for j := 0 ; j < 3 ; j++ {
             c[i][j] = i + j
         }
     }
     fmt.Println( "2d: " , c)
}